Render incoming Reactions

ts/components/_util.ts

@@ -1,5 +1,21 @@
 // A separate file so this doesn't get picked up by StyleGuidist over real components
 
+import { Ref } from 'react';
+import { isFunction } from 'lodash';
+
 export function cleanId(id: string): string {
   return id.replace(/[^\u0020-\u007e\u00a0-\u00ff]/g, '_');
 }
+
+export function mergeRefs<T>(...refs: Array<Ref<T>>) {
+  return (t: T) => {
+    refs.forEach(r => {
+      if (isFunction(r)) {
+        r(t);
+      } else if (r) {
+        // @ts-ignore: React's typings for ref objects is annoying
+        r.current = t;
+      }
+    });
+  };
+}